I am not sure if anyone discussed the following points. Having read through the entire thread (over several weeks), I cannot recollect what has puzzled me a lot with the reporting by crew.
1. The previous sector the Stick-shaker, was continuously working through out the flight.
2. They stopped the Trim actuation (MCAS) by stab cutout switches.
3. They flew the aircraft manually the whole sector.
Why the crew did not write these down in Tech Log. For me with over 40 years as an engineer, this reporting astonishes me. It is not enough if you speak to the guy you meet on arrival of flight. He may not be the guy who really works later on the aircraft in trying to rectify. These are not defects that are just to be passed on verbally, or as just a crew report to operations.
I will mention an instance in my career. The aircraft, a Boeing, experienced pulling to the right during landing roll. The Captain wrote in the Tech Log the defect and a statement "This aircraft is "Un-airworthy' in capitals. What he meant, when I asked him, is that on a wet runway, this aircraft can land in the ditch, as the pulling is severe. He did not have to tell me more.
I am somewhat sure that if the crew had mentioned these 3 defects above in Tech Log, the ill-fated crew on the next flight, might have dealt with the same problem differently. I think. Any comments?